This project encompasses a wide scope of statistical collaboration and consultation with Laboratories and Branches within the Division of Intramural Research (DIR), and with other neuroscience units outside NIH. Particular consideration is given to statistical planning and design of experiments, statistical analysis of data, and statistical inference. Examples of current studies include: clinical studies cholesterol- lowering agents in Neimann-Pick disease, clinical course and outcome of patients with Neimann-Pick disease, clinical studies of Ceredase(TM) in Gaucher's disease (Developmental and Metabolic Neurology Branch); clinical trials of felbamate for the treatment of intractable complex partial seizures, measurement of the effect of time from last seizure and seizure type on metabolic change as measured by PET, clinical trial of prednisone for the treatment of post-polio muscle atrophy, statistical analysis of shape and spatial relationships of maps of the cerebral cortex based on EMG responses to electromagnetic stimulation of the scalp, evaluation of IV. /IG efficacy in dermatomyositis and polymyositis, study of epilepsy progression to general tonic-clonic seizures, three clinical trials of IV/IG in neuromuscular disorder (Medical Neurology Branch); development of time series models for the effect of weather and light on mood in patients with seasonal affective disorder (NIMH): optimal sampling procedures to estimate the size of a population of neuron cells (Clinical Neuroscience Branch); examination of the relationship between MRI change and clinical status in relapsing-remitting MS, clinical trial of the effect of cyclosporine on lesion development in relapsing-remitting MS, modeling lesion recurrence in relapsing-remitting MS, evaluation of the effects of TGF-B and anti-TGF-B on chronic relapsing EAE (Neuroimmunology Branch); statistical modeling of time-to-motor response complication in L-dopa treated patients with Parkinson's disease (Experimental Therapeutics Branch); prevalence of neurologic diseases in the Navajo tribe (Epilepsy Branch); incidence study of primary intracranial neoplasms in Israel; validation study of consultations provided by U.S. drug information centers; case-control study of hemorrhagic stroke and alcoholism in Santiago, Chile; and a prevalence survey of major neurologic disorder in Junin, Argentina.